Database
What is NoSQL?
Non-relational databases designed for flexible schemas, horizontal scaling, and specific data models.
Definition
NoSQL databases provide alternatives to relational (SQL) databases for specific use cases. Types include: Document stores (MongoDB, Firestore) — JSON-like documents; Key-value stores (Redis, DynamoDB) — fast lookups; Column-family (Cassandra, HBase) — wide-column storage; Graph databases (Neo4j) — relationship-heavy data. NoSQL databases often sacrifice strict consistency (ACID) for availability and partition tolerance (CAP theorem).